According to research by Dr. Chandra Suresh, a particular mutation in the brain has caused some people to develop superhuman powers. Additionally, Sylar has targeted evolved humans with the intent of removing their brains.
While giving a lecture at Chennai University, Mohinder Suresh addresses the common misconception that man uses only one-tenth of his brain power. He suggests that with another percent, man may actually be worthy of "God's image".
Brody Mitchum accidentally knocks Claire Bennet in such a way that a tree branch becomes lodged in her brain. She appears dead until the medical examiner removes the branch from her brain. With the branch removed, her power rapidly restores her to health.
At a secret medical facility, Matt Parkman is held captive by Mr. Bennet and a mysterious man. His brain is hooked up to monitors. As Matt attempts to read the minds of his captors, the monitors show increased brain activity.
While perusing his father's research in Sanjog's file, Mohinder comes across an article proclaiming that scientists have found new areas in the brain. The article states that the researchers used DCX imaging to determine that "we all have an area in our brains that functions independently of the other areas".
Dr. Suresh meets with Gabriel Gray and performs tests on his brain. He explains to his subject that the special abilities of evolved humans come from a particular structure of the brain. He also tells Gray that the brain controls every action. Quoting his book, the doctor says that if there's a soul, it's in the brain. Later, in his watch shop, Gabriel realizes how Brian Davis's power of telekinesis originates in the brain. He claims that Davis has a "defect" that he can fix. Gabriel is then compelled to bludgeon Davis over the head.
Charlie reveals to Hiro that she has an blood clot in her brain.
Ando calls Sylar "brain man".
Sandra's headaches prompt a visit to a neurologist.
Zane Taylor is killed and his brain is removed.
Mohinder attaches Sylar to an IV drip. Mohinder says the curare in the drip is a brain paralytic, and keeps Sylar from being able to control his abilities. Mohinder then takes a sample from Sylar's spinal fluid.
Sylar removes the top of Claire's head and examines her brain. Claire asks if he's going to eat her brain, and Sylar says, "That's disgusting". Sylar finds what he needs and replaces Claire's scalp, having taken her ability.
Peter fires a bullet at Arthur, and Sylar uses his ability of telekinesis to interrupt the trajectory, question Arthur, then continue the bullet on its path. Arthur is killed as the bullet enters his brain and goes out the other side. He does not regenerate as the bullet presumably destroyed the spot that controls regeneration.
As Arthur retells his death scene in his own narration, he likes his being shot and killed to that of his son's shooting a deer on a hunting trip during their youth. Unlike the episode, the graphic novel rendering of the gunshot shows his brain being blasted out the back of his head.
Emma looks at a scan of her brain.
When Molly is found by Noah, Quentin and Taylor, they see that she is hooked up to a machine via her brain. Noah postulates that Erica has found a way to access a person's abilities through their brain like Sylar. When Molly wakes up, she shoots herself in the brain to make sure that nobody can exploit her ability again.
- The serial killer Sylar has removed the brains of many of his victims. There is a high correlation between victims of brain removal and Dr. Suresh's list of evolved humans. Known victims include Charlie Andrews and James Walker (Fallout); Brian Davis was murdered by Sylar, but his brain removal is not absolutely confirmed (Six Months Ago). During a brief visit to the future, Hiro Nakamura saw the body of Isaac Mendez with its brain removed (Don't Look Back). Sylar mistook Jackie Wilcox for an evolved human and murdered her but turned his attention to Claire Bennet before proceeding with Jackie's brain removal (Homecoming).
- Based on Dr. Suresh's theories, the wide range of special abilities that evolved humans have demonstrated all originate in the brain, even those that would logically seem to be unrelated to brain development, such as enhanced strength and rapid cell regeneration. (Six Months Ago)
- Mohinder mentions the common perception that humans only use one-tenth of their brain capacity (Genesis). This "statistic", however, is untrue. However, Mohinder seems to use this common misconception as more of a metaphor that evolutionary development of the brain is on the verge of something extraordinary.
- Many medical charts found on primatechpaper.com feature information about the brain.
- Hana's chart notes that she has overlapping visual cortex cells, an enlarged occipital lobe, and abnormal neuron clusters.
- Matt's chart notes that he can hear frontal lobe activity, and that he may have a "21 mutation" and "hypertrophy" in the "Broadman 41" area of his brain.
- Sylar's chart notes that he has enlarged frontal lobes, an irregular hypothalamus, and has been attached to a shunt.
- Mohinder makes an important discovery about Sylar's brain chemistry by examining his spinal fluid. (Parasite)
- When examining Claire's brain in The Second Coming, Sylar was able to find what he sought without actually removing her brain from her head. Only the top half of her brain was exposed, indicating that the critical parts for Sylar's examination are in the cerebrum. When he was examining Candice's brain in Kindred, he made an opening in the back of her skull. The part of the brain that controls evolved human abilities is therefore presumably near the top of the back of the human brain.
- NBC Nightly News's Brian Williams appears on a television in Le Bar; his name is misspelled "Brain". (War Buddies, Part 1)
Sylar's apartment contains medical texts...
...with exposed brains.
(One Giant Leap)
Matt's brain bleeds when an information transfer overloads his body.
(The End of Hana and Drucker)
Emma looks at a scan of her brain.
Most of the Assignment Tracker 2.0 profiles contain a cranial imaging diagram for the profile's subject. These include cranial imaging diagrams for:
- For other uses of brain, see brain (disambig).
- For more information on Sylar's propensity for removing brains, see brain removal.
- For more information about the research in Chandra Suresh's book, see Activating Evolution.